Fabric, paper, leather, or the like



'r. SHEPHERD FABRIC; PAPER, LEATHER, OR THE LIKE May 3, 1933-.

2 She ets-Sheet 1- Filed March 29, 1955 ig/a Maia? fr. SHEPHERD FABRIC,PAPER, LEATHER, OR THE LIKE Filed March 29, 1935 t 2 Sheets-Sheet 2Patented May 3, 1938 UNITED STATES PATENT OFFICE,

rAnamrnrr-m, 23221:. on v I Application March 29, 1935, Serial No.13,756

. In Great Britain June 11, 1934 3 Claims. (01. 1-50) This inventionrelates to fabrics, paper, leather or the like and the manufacturethereof, such fabrics being of the known type in which an extensiblefabrichas imprinted thereon a line or 5 other open pattern of rubber,preferably an aqueous dispersion of latex. This pattern is then driedand vulcanized and it will be found, when the fabric is stretched in anydirection, that it will always return to normal shape and size. The sameresult will be obtained when a multilayer fabric is made. work patternis imprinted on one'layer of fabric, a second layer is pressed on to thestill tacky pattern, thus forming a two layer fabric. A further modifiedform of multifabric may beformed by placing between two sheets of fabriceach bearing an open work pattern, an intermediate solidified open worklayer of coagulated material formed from an aqueous dispersion of latex,con- 20 verted rubber or the like.

Whilst such fabrics are quite successful in practice, there is atendency that when theopen work pattern is being printed, the lines ofthe pattern may be blurred and uneven this being 25 due partly to anexcess of rubber solution being used and partly to the differentabsorbent qualities of the sheets of fabric.

The object of the invention to be hereinafter described is to overcomethese disadvantages.

30 To this end the invention will now be described with reference to theaccompanying drawings in which:-

Figure 1 is a perspective view of a known form of multifabric, i. e. inwhich an open solidified network is arranged between two fabric layerseach being imprinted on their adjacent faces with an open work pattern.

Figure 2 is a side elevation of an engraved printing roller used inpreparing the multifabric 40 in Figure 1.

Figure 3 is a plan view of a network forming a part of the fabric inFigure 1.

Figure 4 is a perspective view of an improved 45 form of two-ply fabricmade accordingtothe invention; i

Figures 5 and 6 are perspective views of two kinds of printing rollersthat may be used;

Figure 7 is a diagrammatic view of an appa- 50 ratus whereby theinvention may be carried into effect; v

Figure 8 is a transverse section of Figure 6 showing a portion of theroller drawn to an enlarged scale; and

55 Figure 9 is a view similar to Figure 8 but in In that case after theopen which the recesses in the roller are modified in shape.

Figure 10 is plan view of a modified form of fabric with one of thelayers turned back.

In the manufacture of a fabric shown in Fig- 5 ure 1, and referring alsoto Figures 2v and 3, a network I: as shown is prepared from coagulablematerial and for this purpose a suitable solution such as an aqueousdispersion of latex, converted rubber or the like is fed to an engraved10 printing roller b shown in Figure 2. The roller b is formed wlthaseries of crossgrooves or recesses 0 extending both longitudinally andcircumferentially, helically or otherwise so as to form a network. Witha printing roller b arranged as shown in Figure 7, it is fed by means ofa transfer roller d which dips into a bath e containing the latex. Afterthe rollerb has picked up the solution a doctor blade I wipes over thesurface of the printing roller b and leaves the solution in the groovesc. A moving blanket 9 passes round the roller h, and the printing rollerrotatesin contact with the moving blanket and prints thereon the networklines of solution contained-in the grooves. The blanket passes on andmeans are provided whereby the printed network k (Figure 3) issubsequently dried and vulcanized in any usual way. After this thefinished network is separated from the blanket and it is now inserted asshown in Figure 1 between .30 two layers of extensible fabric 1, m, forinstance stockinette which have. each been previously treatedby aprinting process by a printing roller similar to b, Figure 2, but inwhich the grooves are obliquely arranged, by which a pattern 11. asshown by the dotted diagonal crossing lines, of adhesive solution isapplied to the adjacent surfaces of the two layers Z, m of stockinette.A sort of sandwich construction is thus obtained comprising two layersof stockinette for example and the interposed solid network It. Thewhole is then subjected to pressure by means of rollers, a press or thelike so as to cause the three layers to adhere to each other veryintimately and tightly by means of the adhesive solution pat- 5 tern n.The resultant fabric is then suitably dried and/or cured or vulcanizedwith the result that astro'ng composite fabric is obtained which, Iafter being extended orstretched, will always contract back to normalsize.

It has been found in practice, with such a known fabric, that in regardto the printing process described both for the solidified network It aswell as adhesive solution pattern n Fig. 1 that in order to prevent airbubbles being formed and to. obtain a smooth and uniform line, regardmust be had to the viscosity of the aqueous dispersion of latex orsimilar solution as well as the dimensions of the grooves or recesses cof the engraved printing roller 21. For this purpose the latex or rubbersolution which is used is much more liquid in character than is usualwith solutions of this kind, 1. e., it possesses a fluidity approachingthat of milk and the following is a typical example of a suitable mixwhich will yield good results:-

a v rts by weight Latex 180 Sulphur 2.25 Zinc oxide 3.0 Accelerator 0.75Anti-oxidant 0.5 Casein solution 10% 5.0

Such a fluid possessesan advantage over the comparatively thick paste orcream that is often used, because it will not result in the presence ofair bubbles during the printing operation owing to its low viscosityvalue and again the lines or patterns printed on the fabric will beuniform and possess sharply defined edges.

To obtain such an improved printing result, a machine may be usedsimilar to that already described and shown in Figure 'l in which arepresents a travelling blanket or a length of fabric to be printed.

In the enlarged sectional view in Figure 8. two groovesv are shown inthe surface of the printing roller 2), such grooves being noted by q andr respectively.

It is to be noted that the grooves are shown as V shape, the depth ofwhich is substantially equal to the width at the mouth so that when theprinting roller b is in contact with the sheet of material a, capillaryattraction will have an influence so as to regulate the amount ofsolution which will be taken out of the grooves during the printingcontact. Whilst any suitable dimensions of depth and width may be used,it has been found in practice that a groove having a depth and widthboth 1/25th of an inch has given good results. The groove q shown inFigure 8 is intended to illustrate it being full of solution before theprinting operation whilst the groove r shows the condition'of the samegroove after printing has occurred and it willbe noticed that in thelatter groove 1' about one third of the quantity or charge of solutionis left remaining in the groove after the printing operation; that is tosay, by the printing contact only a .predetermined quantity of solutionis transmitted to the fabric whereby only just enough will be suppliedfor the purpose and there will be no excess which would result in thelines printed upon the fabric being somewhat uneven and non-uniform.

I By therefore carefully determining the size of the grooves beforehandin relation to the degree of viscosity of the solution, the exact amountof mixture is transferred to the fabric during the printing operationand no more. Thus, there'will be no excess transferred and in order tostill further control the printing operation it is preferred to soak thefabric before the printing with a very weak acid solution to prevent therubber print from too much penetration and to cause it to lie upon thesurface rather than soak into it. A suitable solution for this purposemay be one half to two per cent. of acetic acid and the cloth or fabricso'soaked is semi-dried and then printed. In the two-ply fabricillustrated in Figure 4 such acid solution is, indicated by the hatchedlines s.

In Figure 9 is shown a modified form of groove in the printing cylinderand in this case the grooves are somewhat rectangular in shape and havea width about three times greater than the depth of 1/25th of an inch.In this case the bottom of the groove is serrated as shown at t,

whereby the same feature of retaining a part of the solution in thegroove will be maintained as the serrations will form extended surfacecontact by which capillary attraction is increased to keep back-thedesired amount of. solution. .Such serrations are useful in the caseillustrated where the grooves aresubstantially rectangular in shape. Itis to be noted however that the above dimensions are given by way ofexample only.

Although in Figures 5 and 6 two examples are shown of printing rollers,one in which the grooves are circumferential and the other in Figure 6where the grdbves are longitudinal, it is to be understood that anyother shape of groove or arrangement or design may be used, the crosssection of the grooves shown in such rollers being of the charactershown in Figure 8 or 9 or such other section as will produce the resultdesired of keeping back a certain part of the solution.

It is also to be understood that for printing the solidified network Itgrooves will be used of a capacity relatively greater than thoseemployed to print the adhesive line pattern 11..

From the foregoing it will be understood that an extensible fabric ofthe kind referred to may be obtained by the means described andillustrated, such fabric being permeable both to m0is ture and air sothat adequate ventilation is en sured. Such a fabric may be alsoimproved by replacing the solidified network It by a flexible andelastic or non-elastic fabric consisting of a woven, knitted, braided orlace network of rubber or contractile threads and with or withoutordinary textile threads such as cotton, silk, artificial silk or linencombined therewith, such textile threads being suitably treated (as bytwisting) to allow for the stretching movements.

. A compound fabric of this kind (see Figure 10) maybe easily made byapplying upon an extensible or non-extensible fabricl a layer formed ofsolidified network It. Upon this network there is laid atextile fabric 0already interwoven with elastic threads p, the adjacent surfaces of thelayers having applied thereon a pattern n of adhesive solution.

Having now described my invention. what I claim as new and desire tosecure by Letters Patent is 1. In apparatus for use in manufacturingelastic fabric, a reservoir for liquid coagulable material, a feed, rollpartly immersed therein, a printing roll contacting said feed roll, apressure roll mounted adjacent said printing roll in such a manner as topermit a fabric sheet to pass therebetween, said printing roll havinggrooves in the periphery thereof, said grooves being substantiallyV-shaped and the depth of each being substantially equal to the widththereof at the mouth whereby said grooves hold approximately onethird ofthe liquid material therein by capillary attraction when the exposedsurface of the liquid within the grooves engages the fabric sheet.

2. Apparatus as claimed in claim 1 wherein the depth of the grooves andthe width thereof at the mouth are approximately 1/25th of an inch.

3. In apparatus for use in manufacturing elastic fabric, a reservoir forliquid coagulable material, a feed roll printing roll contacting saidfeed roll, a pressure roll rotatably mounted adjacent said printing roll'so as to. permit a fabric sheet to pass therebepartly immersed therein,a

tween, said printing, roll having grooves in the peripheral surfacethereof, said grooves havinli rounded conical cross-sections whereby thegrooves holda portion 01' a liquid material by capillaryattraction-within the grooves when the exposed surface or the liquid iscontacted by the fabric sheet. 'm oms LEWIS smnnnn. p

